import React, { Component } from 'react';


class Clock extends Component {
  constructor(props) {
    super(props)
    this.state = {date:new Date()}
  }
  componentDidMount() {
    this.TimerID = setInterval(
      () => this.tick(),
      1000
    )
  }
  componentWillUnmont() {
    clearInterval(this.timerID)
  }
  tick() {
    this.setState({
      date: new Date()
    });
  }
  render() {
    return (
      <div>
        <h1>Hello,world</h1>
        <h2>Tt is {this.state.date.toLocaleTimeString()}</h2>
      </div>
    );
  }
}

export default Clock;